Sunday, January 23, 2011

Chemistry-Schemistry

A friend posed this question on facebook recently: What advice would you give your 14 year-old self?

I'd tell myself: Pay more attention in History, Geometry, and Chemistry. But, yeah, you're right about Home Economics. It is just a bunch of malarkey which you'll eschew later....big time.

The only reasons I passed high school Chemistry with Mr. L, the instructor, were because my older brother aced every test (including the first one which tested your current knowledge of the subject) and was therefore well-adored by Mr. L; and he knew my mom, who was a substitute teacher.

Oh, and if you were female and gave Mr. L a hug every time you saw him, you'd pass.

Bring it on, big guy.

But, had I paid more attention in class, I would already understand properties of metal. Instead, I'm studying up on it like crazy so I can use it to gussy up my shop-made tools.

First on my list is to make a level. I bought four at the Brown Dealer Show and Auction yesterday—three for inspiration and one to tear apart.

And I bought five Swiss-made gravers. I was so desperate to try them on brass when I got home, I used the doorknob to my workshop.

The levels include: Stanley Rule & Level Co., 1896, cherry, 30"; E. Preston & Sons, (no date, but probably c. 1900), rosewood 24"; Davis & Cook, 1886, mahogany, 24"; and one we shall refer to as "donor."

By the looks of these, at least some levels secured vials in place with plaster, and better ones included adjustment screws. I'll learn more once I receive Don Rosebrooks' book about American-made levels.

I ordered a sheet of brass from McMaster-Carr. According to their site, the brass listed as Alloy 353 is a good choice for engraving.

In my research, I found that brass is an alloy of copper and zinc. "Alloy" refers to a metal consisting of two or more materials, one of which must be a metal.

But then, you probably paid attention in class and already knew that.

20 comments:

Charles said...

Congrats on your new toys! Can't wait to see your engraving creations.

But seriously... you would say "you'll eschew later..." to your 14-year old self?

I'm still working on learning what eschew means. :-P

Dyami said...

Kari,
Good luck on your journey into metal. It is another medium I love to work with (though its been years). While I'm no metalurgist, I did learn sheet metal fabrication at work. If you run into any issues, let me know. I'll certainly try to help.

Larry Marshall said...

Oh boy...Kari's going to be taking her carving skills to metal. Can't wait to see the results. Graveurs are really great as mini-mortising chisels when doing miniatures too :-)

Cheers --- Larry

Stephen Shepherd said...

Kari,

Sounds like a fun project, are you getting red or yellow brass?

Stephen

The Village Carpenter said...

Charles, if my 14 y.o. self would ask me what "eschew" means, I would say "look it up." (in my grandmother's voice)

Dyami, it does seem like woodworking and metalworking go hand-in-hand. Thanks for the offer.:o)

Larry, I can definitely see how they would work well with miniatures.

Stephen, uh...I guess I didn't get that far in my research. What's the difference?

Trevor Walsh said...

Kari,
I've done some research into making levels. Even got a pair of vintage Stanley vials for it... A material called "Water Glass" was also used to place the vials. It's a Silica something compound that hardens like plaster but doesn't break down like plaster does. I've been collecting the silica gel packets to make the stuff for a bit now.

Trevor

Mitchell said...

Ouu, ouu, I know, I know, I know this one. Ask me, ask me.

Yes ma'am.

The difference between yellow and red brass is the amount of zinc in it. The more zinc the composition has, the yellower and lighter it becomes.

Yellow brass is made up of 30 to 35% zinc and 65 to 70% copper.

Red brass would have a make-up of 15 to 20% zinc and 80 to 85% copper.

The less zinc in the composition, the harder the metal.

Add in a little tin to a red brass recipe and you have gunmetal.

Your welcome Mr. Kotter...er....Ms. Hultman.

John Cashman said...

One thing you'll want to watch with brass is that it becomes work-hardened. Simply put, the more you shape it, the harder it gets. It will get very brittle. Just like steel, a given alloy of brass has a range of hardnesses. It's very easy to anneal. Simply heat the brass with a torch. Unlike steel, you can either let the brass cool slowly, or you can quench it to cool quickly. Either way, the brass will be much softer. My guess is if you try annealing a piece before you engrave it, it will be much easier to work.

John Cashman said...

Oh. If you heat it too much, you'll cook some of the zinc off of the surface, leaving mostly copper behind. This will give the surface a more reddish color, as Mitchell noted above. But don't worry, it's not easy to do, and it's only skin deep. But it can also give some nice color variation if that's what you want.

The Village Carpenter said...

Ah, now see? I count on you guys to teach me stuff and you never disappoint. Thanks so much for all the help!

Ian W said...

Kari,
I have nothing to teach, but much to learn. It is very good to have you back, I hope your blog holiday was a good one.
cheers,
Ian W

Douglas said...

Kari,
Woodstore.net has a $2 plan for a wood and brass torpedo level.

losey

The Village Carpenter said...

Thanks, Ian. Good to be back. :o)

Douglas, thanks for the link! I found this right after I put up the blog post and bought the plans for reference.

GregM said...

Any alloy consisting primarily of copper and zinc is referred to as "brass", but there are all kinds of other elements that can be added in trace amounts to change its appearance and properties. Unfortunately, terms like "soft brass", "naval brass", "red brass", etcetera are used loosely and imprecisely and don't always mean the same thing to different people. There is some good information on different types of brass here : http://www.onlinemetals.com/brassguide.cfm

I've used quite a bit of brass in small quantities for parts such as ferrules or wear plates on restored or shop-made tools, but I've never purchased virgin metal. My sources are discarded plumbing and electrical parts and decorative knick-knacks picked at at yard sales. Some is softer, some harder; some quite malleable and some almost crystalline. I'm no machinist and am not producing high-tolerance engineering-critical parts. For my purposes - and yours too - I don't think it really matters.

"Water glass" is the common name for sodium metasilicate - a chemical with many commercial and industrial uses (inculding preserving eggs). I don't know much about levels but I was once a chemist, and Trevor, I think you may be mistaken. I don't think water glass would be at all suitable for mounting vials. Perhaps there is confusion with the archaic use of the word "water glass" to descible the bubble tubes or vials themselves. Kari, I think you'd be best sticking with plaster of paris.

Level vials are mounted in one of two ways - fixed vials, which are set in a bed of plaster, or adjustable vials which have complex spring-loaded, screw-adjusted mechanisms. You are probably best off sticking to the fixed vials!. Herbet Keen's book "Restoring Antique Tools" has some useful information about repairing vintage levels, including vial replacement.

You can probably buy new vials from various sources, but I would suggest that you look for a donor level - some poor beat-up, cast-off reject. This approach appeals to me on so many levels (recycling, "green", giving the soul of an old tool new life, potential steampunk factor, etc).

I wish you luck with your project, and look forward to following your progress and seeing the final results her on the blog. As always, you are an inspiration to us all.

The Village Carpenter said...

Greg, thank you for the information and the link. I was actually thinking about using silicone sealant to keep the vial in place, instead of plaster (mainly because I have some of that). I took apart one of the levels with an adjustment screw and was surprised to see what a tricky mechanism it was. So, yeah, I've pretty much decided to make a fixed level. :D

Gary Roberts said...

Oh Oh, Kari is becoming a collector...

Gye Greene said...

Aww.... now, there you go -- dissing Home Ec.

At my middle school, we rotated, by quarter, woodworking, art, cooking, and sewing. (Woodworking: oddly, I didn't learn much and didn't take to it -- but stuff wasn't explained well, I had no specific projects in mind, and you had to wait in line for the machines. Plus, it's hard to get anything done when you're trying to work in 30 minute increments (plus setup, plus cleanup, equals the class period).

Sewing was useful: made a cooking apron for my dad, which he still uses 25+ years later, and learned how to sew a hem, etc.

Cooking was GREAT: afternoon snack time, baby!!! (i.e., you get to **eat** your projects; brilliant!)


--GG

Gye Greene said...
This comment has been removed by the author.
Eric said...

Can't wait to see what you come up with Kari.
I bet it turns out awesome.
Thanks.
Eric

The Village Carpenter said...

Gary, they're for study, not collecting, I tell ya!

Gye, your wife is a lucky lady to have married such a handy fella. :o)

Those comments I delete are spam, in case anyone wondered.

Eric, it's a really fun project, especially shaping the brass. I'm hoping to finish and blog about in the next two weeks.